Files
5chan/.cursor/skills/playwright-cli/SKILL.md
T
Tommaso Casaburi 1a33f7dc88 chore(agents): add a machine-wide Playwright browser resource budget
Playwright disables normal background throttling, so a hidden 5chan page keeps
doing P2P and rendering work after a check finishes. Agents verifying in
parallel across worktrees stacked whole browser engines on one machine.

Add scripts/pw-session.sh, a wrapper that permits one active Playwright browser
at a time and records who holds it:

- The lock is machine-wide, not per-repository, because the contended resource
  is RAM and CPU. Every worktree and checkout shares one slot.
- Acquisition is an atomic mkdir. Stale locks clear themselves: `open` reclaims
  any slot whose recorded browser is no longer `status: open` in
  `playwright-cli list --all`, so an interrupted workflow cannot strand the
  budget. When that list cannot be read the lock is left alone, so a broken CLI
  never silently disables the budget.
- `open` exits 75 when the slot is busy; `--wait[=SECONDS]` blocks instead.
- `close` always stops the browser, even when the lock was already lost, and
  never releases a slot held by a different session.
- `status` reports the holder and whether its browser is still alive.

Agent policy now runs browser engines and profiler batches sequentially, uses
Chrome/Blink during iteration and the full engine matrix only for final
verification, and never uses `close-all` or `kill-all` while other agents may
own sessions.

Covered by scripts/pw-session.test.js.
2026-08-01 19:21:01 +02:00

10 KiB

name, description, allowed-tools
name description allowed-tools
playwright-cli Automates browser interactions for web testing, form filling, screenshots, and data extraction. Use when the user needs to navigate websites, interact with web pages, fill forms, take screenshots, test web applications, or extract information from web pages. Bash(playwright-cli:*), Bash(./scripts/pw-session.sh:*)

Browser Automation with playwright-cli

Resource Budget (MUST)

One Playwright browser session may be active at a time, machine-wide. The budget is shared by every worktree and by any other checkout that ships this wrapper, because the contended resource is machine RAM and CPU rather than the repository. Playwright disables normal background throttling, so hidden 5chan pages keep P2P and rendering work active after a check.

  • During iteration, use Chrome/Blink only. Run the full cross-browser matrix once the change is ready for final verification.
  • Open every fresh session through ./scripts/pw-session.sh open <session> ...; it acquires the shared browser slot.
  • Reuse the same engine session for desktop and mobile by resizing it.
  • Close it with ./scripts/pw-session.sh close <session> in a finally-style cleanup before opening another engine. close stops the browser even when the lock was already lost, so it is always the right cleanup call.
  • Run browser engines and profiler batches sequentially. Never spawn browser-driving agents in parallel.
  • Exit code 75 means the slot is busy. Finish non-browser work and retry, or block on ./scripts/pw-session.sh open --wait[=SECONDS] <session> ... (default 300s). Do not bypass the lock.
  • Never use playwright-cli close-all or kill-all while concurrent agents may own sessions.
  • A lock left behind by an interrupted workflow clears itself: the next open reclaims any slot whose browser is no longer running. Inspect the holder with ./scripts/pw-session.sh status, which reports whether that browser is still alive. release <session> is a last resort for the rare case where status cannot verify the browser state.

Cross-Browser UI Verification

When using playwright-cli to verify rendering, styling, layout, or interactions in this repo, run the relevant flow in all three major browser engines:

  • chrome for Blink
  • firefox for Gecko
  • webkit for Safari/WebKit coverage

Use separate short named sessions per engine, compare the results, and record any engine-specific differences instead of treating Chromium output as sufficient. Run them sequentially:

./scripts/pw-session.sh open verify-chrome http://example.com --browser=chrome
# Run the desktop and mobile flow, then release the slot.
./scripts/pw-session.sh close verify-chrome

./scripts/pw-session.sh open verify-firefox http://example.com --browser=firefox
# Run the desktop and mobile flow, then release the slot.
./scripts/pw-session.sh close verify-firefox

./scripts/pw-session.sh open verify-webkit http://example.com --browser=webkit
# Run the desktop and mobile flow, then release the slot.
./scripts/pw-session.sh close verify-webkit

Quick start

# open new browser
playwright-cli open
# navigate to a page
playwright-cli goto https://playwright.dev
# interact with the page using refs from the snapshot
playwright-cli click e15
playwright-cli type "page.click"
playwright-cli press Enter
# take a screenshot
playwright-cli screenshot
# close the browser
playwright-cli close

Session mode selection

Default to a fresh isolated browser session for reproducible verification.

Before browser work where existing state may matter, explicitly confirm the mode if the user has not already said which one they want:

  1. Fresh isolated playwright-cli session
  2. Current browser session reuse

Existing state usually matters when the task depends on auth, cookies, extensions, open tabs, or reproducing something already happening in the contributor's browser.

Do not attach to a live personal browser session without explicit approval.

If current-session reuse is requested, prefer the supported attach path in the local setup:

# Fresh isolated browser (default)
playwright-cli -s=verify open https://example.com

# Reusable Playwright-managed profile
playwright-cli -s=verify open https://example.com --persistent

# Attach to an existing browser when the local extension bridge is set up
playwright-cli open --extension

If the task requires the contributor's current browser session and the attach path is not available in the current setup, stop and ask whether to switch to a fresh session or provide an explicit CDP-based Playwright script.

Commands

Core

playwright-cli open
# open and navigate right away
playwright-cli open https://example.com/
playwright-cli goto https://playwright.dev
playwright-cli type "search query"
playwright-cli click e3
playwright-cli dblclick e7
playwright-cli fill e5 "user@example.com"
playwright-cli drag e2 e8
playwright-cli hover e4
playwright-cli select e9 "option-value"
playwright-cli upload ./document.pdf
playwright-cli check e12
playwright-cli uncheck e12
playwright-cli snapshot
playwright-cli snapshot --filename=after-click.yaml
playwright-cli eval "document.title"
playwright-cli eval "el => el.textContent" e5
playwright-cli dialog-accept
playwright-cli dialog-accept "confirmation text"
playwright-cli dialog-dismiss
playwright-cli resize 1920 1080
playwright-cli close

Navigation

playwright-cli go-back
playwright-cli go-forward
playwright-cli reload

Keyboard

playwright-cli press Enter
playwright-cli press ArrowDown
playwright-cli keydown Shift
playwright-cli keyup Shift

Mouse

playwright-cli mousemove 150 300
playwright-cli mousedown
playwright-cli mousedown right
playwright-cli mouseup
playwright-cli mouseup right
playwright-cli mousewheel 0 100

Save as

playwright-cli screenshot
playwright-cli screenshot e5
playwright-cli screenshot --filename=page.png
playwright-cli pdf --filename=page.pdf

Tabs

playwright-cli tab-list
playwright-cli tab-new
playwright-cli tab-new https://example.com/page
playwright-cli tab-close
playwright-cli tab-close 2
playwright-cli tab-select 0

Storage

playwright-cli state-save
playwright-cli state-save auth.json
playwright-cli state-load auth.json

# Cookies
playwright-cli cookie-list
playwright-cli cookie-list --domain=example.com
playwright-cli cookie-get session_id
playwright-cli cookie-set session_id abc123
playwright-cli cookie-set session_id abc123 --domain=example.com --httpOnly --secure
playwright-cli cookie-delete session_id
playwright-cli cookie-clear

# LocalStorage
playwright-cli localstorage-list
playwright-cli localstorage-get theme
playwright-cli localstorage-set theme dark
playwright-cli localstorage-delete theme
playwright-cli localstorage-clear

# SessionStorage
playwright-cli sessionstorage-list
playwright-cli sessionstorage-get step
playwright-cli sessionstorage-set step 3
playwright-cli sessionstorage-delete step
playwright-cli sessionstorage-clear

Network

playwright-cli route "**/*.jpg" --status=404
playwright-cli route "https://api.example.com/**" --body='{"mock": true}'
playwright-cli route-list
playwright-cli unroute "**/*.jpg"
playwright-cli unroute

DevTools

playwright-cli console
playwright-cli console warning
playwright-cli network
playwright-cli run-code "async page => await page.context().grantPermissions(['geolocation'])"
playwright-cli tracing-start
playwright-cli tracing-stop
playwright-cli video-start
playwright-cli video-stop video.webm

Install

playwright-cli install --skills
playwright-cli install-browser

Configuration

# Use specific browser when creating session
playwright-cli open --browser=chrome
playwright-cli open --browser=firefox
playwright-cli open --browser=webkit
playwright-cli open --browser=msedge
# Connect to browser via extension
playwright-cli open --extension

# Use persistent profile (by default profile is in-memory)
playwright-cli open --persistent
# Use persistent profile with custom directory
playwright-cli open --profile=/path/to/profile

# Start with config file
playwright-cli open --config=my-config.json

# Close the browser
playwright-cli close
# Delete user data for the default session
playwright-cli delete-data

Browser Sessions

# create new browser session named "mysession" with persistent profile
playwright-cli -s=mysession open example.com --persistent
# same with manually specified profile directory (use when requested explicitly)
playwright-cli -s=mysession open example.com --profile=/path/to/profile
playwright-cli -s=mysession click e6
playwright-cli -s=mysession close  # stop a named browser
playwright-cli -s=mysession delete-data  # delete user data for persistent session

playwright-cli list
# Never use these during concurrent agent work; they affect unrelated sessions.
# Close all browsers
playwright-cli close-all
# Forcefully kill all browser processes
playwright-cli kill-all

Example: Form submission

playwright-cli open https://example.com/form
playwright-cli snapshot

playwright-cli fill e1 "user@example.com"
playwright-cli fill e2 "password123"
playwright-cli click e3
playwright-cli snapshot
playwright-cli close

Example: Multi-tab workflow

playwright-cli open https://example.com
playwright-cli tab-new https://example.com/other
playwright-cli tab-list
playwright-cli tab-select 0
playwright-cli snapshot
playwright-cli close

Example: Debugging with DevTools

playwright-cli open https://example.com
playwright-cli click e4
playwright-cli fill e7 "test"
playwright-cli console
playwright-cli network
playwright-cli close
playwright-cli open https://example.com
playwright-cli tracing-start
playwright-cli click e4
playwright-cli fill e7 "test"
playwright-cli tracing-stop
playwright-cli close

Specific tasks